Kansas planting calendar

When to plant rhubarb in Kansas — sow, transplant & harvest dates

Kansas is mostly USDA zone 6b (range 5b-7a). Dates below are derived from rhubarb's frost tolerance and Kansas's frost window — not generic national averages.

Rhubarb planting timetable for Kansas

Stage	When in Kansas	Anchor
Direct-sow outside	late March (March 25)	21 days before the last frost (mid-April)
First harvest (estimate)	late September (September 23)	~547 days from direct sow

Dates are state-wide averages for the dominant zone. Local microclimates — elevation, urban heat, coastal moderation — can shift the window by 1-2 weeks. Use the frost-date calculator for a date tuned to your town.

Why Kansas's climate shifts the rhubarb dates

Kansas's last spring frost averages mid-April and first fall frost late October, which sets the whole planting clock. Kansas has a long, hot, often windy continental season. Heat and drought stress matter as much as the winter low across the state. Wait for warm soil — rhubarb stall in cold ground even after the air warms, so don't rush them out.

Rhubarb is planted as divisions or crowns in early spring while the soil is still cool, 2-3 weeks before the last frost; it is extremely cold-hardy and actually requires winter chilling to break dormancy (reliably hardy to zone 3, marginal in zones 9-10 where inadequate chilling reduces vigour). Do not harvest in year one; take only 2-3 stalks per plant in year two; harvest freely from year three onward, always leaving at least 3-4 strong stalks per crown. Never eat the leaves — rhubarb foliage contains toxic oxalates at harmful concentrations.

Frost-risk note

Don't plant before mid-April — a hard freeze can still set young plants back. In the northwest High Plains (zone 5b) the safe date runs a week or two later.

Regional variation within Kansas

the northwest High Plains (zone 5b) runs roughly 1-2 weeks behind the state average; the south-central plains around Wichita (zone 7a) can plant 1-2 weeks earlier.

Wichita — USDA zone 7a
Kansas City — USDA zone 6b
Topeka — USDA zone 6b
Overland Park — USDA zone 6b

What else to plant in Kansas around then

Pair the post-frost slot with other warm-season crops — peppers, beans, squash, and cucumbers.

Quick-grow guide

Sun: Full sun — 6+ hours direct (tolerates light afternoon shade in hot zones).
Soil temperature for germination: Soil 4-10 °C (40-50 °F) at crown planting.
Spacing: 36-48 inches (90-120 cm) between plants.
Days to harvest: ~547 days from planting out.

Frequently asked questions

When is the best time to plant rhubarb in Kansas?

In Kansas (mostly USDA zone 6b), direct-sow rhubarb late March (before the last frost, mid-April), and harvest from late September. Rhubarb are cold-hardy — they tolerate frost and actively prefer cool weather, so they go in well before the last spring frost and bolt in summer heat.

What USDA zone is Kansas?

Most of Kansas sits in USDA hardiness zone 6b, with the state spanning roughly 5b-7a from the northwest High Plains (zone 5b) to the south-central plains around Wichita (zone 7a). The last spring frost averages mid-April and the first fall frost late October.

Can you grow rhubarb in Kansas?

Yes. Kansas's dominant zone 6b supports rhubarb — the key is timing. Rhubarb are cold-hardy — they tolerate frost and actively prefer cool weather, so they go in well before the last spring frost and bolt in summer heat.

Does the planting date change across Kansas?

the northwest High Plains (zone 5b) runs roughly 1-2 weeks behind the state average; the south-central plains around Wichita (zone 7a) can plant 1-2 weeks earlier.

What else can I plant in Kansas around the same time?

Pair the post-frost slot with other warm-season crops — peppers, beans, squash, and cucumbers.

Source and methodology

State zone spans from the USDA Plant Hardiness Zone Map (2023); frost-date averages from NOAA Climate Data Online. Hot-state two-season timing cross-checked against the UF/IFAS Florida Gardening Calendar and the University of Arizona Cooperative Extension planting calendar. Curated by the Growli editorial team.